Bowling ball with improved thumb support

ABSTRACT

A bowling ball is constructed to include a thumb-engagement insert and a thumb-clearance recess positioned radially inwardly of the thumb-engagement insert.

BACKGROUND OF THE INVENTION

The present invention generally relates to bowling balls and more particularly to thumb supporting systems for bowling balls.

Conventional bowling balls may be constructed with drilled gripping holes. A bowler may place his or her thumb in a thumb hole and two other fingers of the same hand into finger holes. By exerting force between the thumb and fingers, the bowler may be able to pick up, hold and control the ball. Each of the holes in a conventional bowling ball is cylindrical. A bowler's gripping force is maintained by frictional force between the fingers and thumb and the cylindrical interior surfaces of the respective holes. In that context, it is important to provide a proper fit between a bowler's fingers and thumb and the respective gripping holes.

It is particularly important to provide a proper fit between a thumb hole and the bowler's thumb. Bowlers need to be able to hold on to the bowling ball securely, but be able to let go of it easily to get the best pin action and control. Some bowlers may use a system of interchangeable thumb inserts or various tapes on their thumbs to be able securely hold on to the bowling ball.

As can be seen, there is a need for a thumb hole gripping system that accommodates a positive engagement between a thumb and a thumb hole and also accommodates a controllable release of the thumb from the thumb hole.

SUMMARY OF THE INVENTION

In one aspect of the present invention, a bowling ball may comprise: a thumb-engagement insert; and a thumb-clearance recess positioned radially inwardly of the thumb-engagement insert.

In another aspect of the present invention, a thumb-engagement insert for a bowling ball may comprise: a cylindrical body; a cylindrical upper interior portion; and a frustro-conical lower interior portion.

In still another aspect of the present invention, a method of constructing a bowling ball may comprise the steps of: drilling a first recess hole with a first diameter in a thumb position of the bowling ball; drilling a second recess hole with a second diameter smaller than the first diameter so that the second recess hole is coaxial with the first recess hole and so that an insert-supporting shoulder is formed; and placing a thumb-engagement insert into the first recess hole so the insert is in contact with the insert-supporting shoulder.

These and other features, aspects and advantages of the present invention will become better understood with reference to the following drawings, description and claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a bowler using a bowling ball configured in accordance with an embodiment of the invention;

FIG. 2 is a perspective view of a bowling ball thumb-engagement insert in accordance with an embodiment of the invention;

FIG. 3 is a cross-section view of the insert of FIG. 2;

FIG. 4 is a cross-sectional view of the bowling ball of FIG. 1;

FIG. 5 is partial cross-sectional view of the insert of FIG. 2 inserted in the bowling ball of FIG. 1;

FIG. 6 is a partial cross-sectional view of the insert of FIG. 2 in a configuration prior to being drilled to accommodate a particular bowler's thumb size; and

FIG. 7 is a flow chart of a method for constructing a bowling ball in accordance with an embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

The following detailed description is of the best currently contemplated modes of carrying out exemplary embodiments of the invention. The description is not to be taken in a limiting sense, but is made merely for the purpose of illustrating the general principles of the invention, since the scope of the invention is best defined by the appended claims.

Various inventive features are described below that can each be used independently of one another or in combination with other features.

Broadly, embodiments of the present invention generally provide a bowling ball with thumb-engagement insert in a thumb hole of the bowling ball.

Referring now to the Figures, it may be seen that an exemplary embodiment of a bowling ball 10 may comprise a thumb-engagement insert 12 positioned in a cylindrical recess 14 of the ball 10. The bowling ball 10 may also be provided with a cylindrical thumb-clearance recess 16. The thumb-clearance recess 16 may be coaxial with the recess 14 and may have a diameter smaller than a diameter of the recess 14. An insert-supporting shoulder 30 may be formed at an intersection of the recesses 14 and 16.

In an alternate embodiment (not shown in the drawings) the shoulder 30 may be formed by boring the thumb-clearance recess 16 and the cylindrical recess 14 at the same diameter. A thin cylindrical sleeve (not shown) having a length equal to the length of the thumb-clearance recess 16 may be inserted into the bored hole. A top of the sleeve may then act as the shoulder 30 to prevent the insert from being pushed into the thumb-clearance recess.

The insert 12 may have a cylindrical body 18. An upper interior portion 26 of the insert 12 may have a cylindrical shape. A lower interior portion 20 of the insert 12 may have a frustro-conical shape. The lower interior portion 20 may be tapered at an angle A of about 30° to about 60° relative to an axis 32 of the insert 12.

Referring particularly to FIG. 4, it may be seen that bowler's thumb 24 may be inserted into the bowling ball 10 so that thumb 24 may pass through the insert 12 and a distal end 24-1 of the thumb 24 may reach into the thumb clearance recess 16. The bowler may bend his or her thumb 24 so that it may engage with the lower interior portion 20 of the insert 12, thus enhancing the bowler's grip of the ball 10.

The bowling balls 10 may be newly constructed to include one of the inserts 12. Alternatively, a pre-existing bowling ball may be retrofitted to include one of the inserts 12.

In an exemplary method of constructing one of the bowling balls 10, one of the inserts 12 may be placed into the ball 10, so that the insert 12 may be subsequently drilled to fit a particular bowler's thumb. Upon initial installation, the insert 12 may have a configuration such as that illustrated in FIG. 6. The insert 12 may have its lower interior portion 20 fully formed. The upper interior portion 26 may be a small diameter hole that is large enough to allow air to escape from the recesses 14 and 16 when the insert 12 may be pressed into the ball 10.

The insert 12 may be installed in the ball 10 by performing the following steps. The recess hole 14 may be drilled in the thumb position of the bowling ball 10. The recess hole 14 may be about 2 inches to about 2½ inches in diameter and may be about one inch to about 1½ inches deep. The recess hole 16 may be drilled coaxially with the recess hole 14. The recess hole 16 may have a diameter smaller than the diameter of the recess hole 14. The recess hole may be about 1 inch to about 1½ inches deeper than the recess hole 14 to provide for thumb-clearance. An adhesive such as Super glue or epoxy may be spread on the inside of the 2″ diameter hole and the insert 12 may be pressed into the hole until it contacts the insert-supporting shoulder 30. Using a ball router (not shown), a top end on the insert 12 may be trimmed to conform to the shape of an outer shell of the bowling ball 10.

Subsequently to insertion of the insert 12, the insert 12 may be drilled so that the upper interior portion 26 may be properly sized for a particular bowler. A transition region between the upper interior portion 26 and the lower interior portion 20 may be smoothed with a bowling ball sander (not shown) to provide a comfortable gripping surface for the bowler's thumb.

It should be understood, of course, that the foregoing relates to exemplary embodiments of the invention and that modifications may be made without departing from the spirit and scope of the invention as set forth in the following claims. 

What is claimed is:
 1. A bowling ball comprising: a thumb-engagement insert; and a thumb-clearance recess positioned radially inwardly of the thumb-engagement insert.
 2. The bowling ball of claim 1: wherein the thumb-engagement insert has a cylindrical upper interior portion with a first diameter; and wherein the thumb-clearance recess is cylindrical and has a second diameter larger than the first diameter.
 3. The bowling ball of claim 2 further comprising a cylindrical recess in which the thumb-engagement insert is positioned, wherein the cylindrical recess has a third diameter larger than the second diameter of the thumb-clearance recess so that the bowling ball is provided with an insert-supporting shoulder.
 4. The bowling ball of claim 1 wherein the thumb-engagement insert has a lower interior portion with a frustro-conical shape.
 5. The bowling ball of claim 4 wherein the lower interior portion is tapered at an angle of about 30° to about 60° relative to an axis of the insert.
 6. The bowling ball of claim wherein the insert is between about one inch and 1½ inches in length.
 7. A thumb-engagement insert for a bowling ball comprising: a cylindrical body; a cylindrical upper interior portion; and a frustro-conical lower interior portion.
 8. The insert of claim 7 wherein the lower interior portion is tapered at an angle of about 30° to about 60° relative to an axis of the insert.
 9. A method of constructing a bowling ball comprising the steps of: drilling a first recess hole with a first diameter in a thumb position of the bowling ball; drilling a second recess hole with a second diameter smaller than the first diameter so that the second recess hole is coaxial with the first recess hole so that an insert-supporting shoulder is formed; and placing a thumb-engagement insert into the first recess hole so the insert is in contact with the insert-supporting shoulder.
 10. The method of claim 9 further comprising the step of drilling the insert to fit a thumb of a particular bowler. 